package apiDay02;

public class LongDemo {
    public static void main(String[] args) {
        String str="";
        long t1 =System.currentTimeMillis();
        for (int i = 0; i <50000 ; i++) {
            str=str+"a";
        }
        long t2=System.currentTimeMillis();
        System.out.println(t2-t1);
    }
}
